1. Field
The following description relates to an optical communication system, and more particularly, to a multi-mode fiber-based optical transmission/reception apparatus and method capable of transmitting different signals according to fiber modes.
2. Description of the Related Art
An optical fiber used for optical communications includes a single-mode fiber and a multi-mode fiber. The optical fiber is characterized by a profile in which at least one core for light propagation is surrounded by a cladding. Since an index of refraction of the core is greater than that of the cladding, light is fully reflected and propagates through the fiber.
A wavelength of propagating light and a core diameter may determine the shape of light, i.e., a mode that can be supported by a fiber. A core diameter of a fiber used in existing optical communications may be 8 μm for a single mode fiber, and 50 μm for a multi-mode fiber. That is, a larger core diameter produces more modes.
The number of propagation modes may be determined by the design of the core size and distribution of refractive index, and a fiber designed to support multiple propagation modes is a multi-mode fiber, or a few-mode fiber (FMF).
In prior art, a single-mode fiber modulates data using laser that generates the single mode and transmits modulated data, whereas a multi-mode fiber modulates data using laser that generates all higher modes and transmits modulated data. However, the multi-mode fiber may provide a short transmission distance up to only several hundred meters for 10 Gb/s signals, due to high mode interference.